Thermal performance of passively cooled pico projector equipped with a fin array

Abstract Three 120-mm × 53-mm × 19-mm pico projectors featuring different thermal designs were fabricated and horizontally tested to examine the thermal resistance from the heater that was attached to the fin array base in the test pico projector to the ambient. Either a 7-plate fin array or a 37-pin fin array was installed in each test pico projector. The heat transfer coefficient of the fin array in the test pico projector under various conditions was also estimated based on the analysis of a thermal resistance network. The measured results showed that Case-A had the highest thermal resistance while Case-C yielded the lowest thermal resistance. At an input power of 7 W, the thermal resistances of Case-A, Case-B and Case-C having a pin-fin array were 16.3, 15.5 and 15 °C/W, respectively, while the thermal resistances of Case-A, Case-B and Case-C having a plate-fin array were 16.6, 16 and 14.8 °C/W, respectively. The heat transfer coefficient of the plate-fin array in Case-B was higher than that in Case-A due to the extra top openings, whereas the heat transfer coefficient of the pin-fin array in Case-B was similar to that in Case-A because the spacing between pins was so tiny.

[1]  G. Ellison,et al.  Maximum thermal spreading resistance for rectangular sources and plates with nonunity aspect ratios , 2003 .

[2]  Jin-Cherng Shyu,et al.  Plate-fin array cooling using a finger-like piezoelectric fan , 2014 .

[3]  Xu Jingyuan,et al.  An analytical solution of thermal resistance of cubic heat spreaders for electronic cooling , 2004 .

[4]  Jin-Cherng Shyu,et al.  Thermal management of pico projector using a piezoelectric fan , 2015 .

[5]  Mehdi Mehrtash,et al.  Natural convection heat transfer from inclined plate-fin heat sinks , 2013 .

[6]  M. Yovanovich,et al.  Thermal Spreading Resistance of Eccentric Heat Sources on Rectangular Flux Channels , 2000, Heat Transfer: Volume 4.

[7]  Kai-Shing Yang,et al.  Orientation effect on heat transfer of a shrouded LED backlight panel with a plate-fin array , 2013 .

[8]  Jin-Cherng Shyu,et al.  Thermal performance of flat vapor chamber heat spreader , 2008 .

[9]  D. W. Van de Pol,et al.  Free Convection Nusselt Number for Vertical U-Shaped Channels , 1973 .

[10]  Kai-Shing Yang,et al.  Thermal characterization of shrouded plate fin array on an LED backlight panel , 2011 .

[11]  H. C. Su,et al.  Investigation of a piezoelectric fan embedded in a heat sink , 2012 .

[12]  W. Rohsenow,et al.  Thermally Optimum Spacing of Vertical, Natural Convection Cooled, Parallel Plates , 1984 .

[13]  M. Yovanovich.  Thermal Resistances of Circular Source on Finite Circular Cylinder With Side and End Cooling , 2003 .

[14]  Jung-Chang Wang,et al.  Development of 30 Watt high-power LEDs vapor chamber-based plate , 2010 .

[15]  E. Radziemska,et al.  Heat transfer by natural convection from an isothermal downward-facing round plate in unlimited space , 2001 .

[16]  Mehdi Mehrtash,et al.  A correlation for natural convection heat transfer from inclined plate-finned heat sinks , 2013 .

[17]  J. R. Culham,et al.  Influence of Geometry and Edge Cooling on Thermal Spreading Resistance , 2006 .

[18]  M. Yovanovich,et al.  Analytical modeling of spreading resistance in flux tubes, half spaces, and compound disks , 1998 .

[19]  Abdul Jabbar N. Khalifa.  Natural convective heat transfer coefficient : a review. I. Isolated vertical and horizontal surfaces , 2001 .

[20]  A. Kraus,et al.  Design of Optimum Plate-Fin Natural Convective Heat Sinks , 2003 .

[21]  Robert J. Moffat,et al.  Describing the Uncertainties in Experimental Results , 1988 .

[22]  Avram Bar-Cohen,et al.  Fin Thickness for an Optimized Natural Convection Array of Rectangular Fins , 1979 .